Pericarditis is a group of polyetiological diseases often associated with emergence of life–threatening conditions. Poor knowledge of underlying cellular mechanisms and lack of relevant approaches to investigation of pericarditis result in major challenges in diagnosis and treatment.The aim of this work was to identify changes in the activity of autophagy in epicardial cells in acute pericarditis.Materials and methods. Acute pericarditis in mice was induced by intrapericardial injection of Freund's adjuvant in the study group (n=15). The control group included animals receiving either intrapericardial injection of phosphate-buffered saline (PBS) (n=15), or sham surgery without injections (n=7). On Days 3 or 5 after surgery the animals were euthanized under isoflurane anesthesia. Immunofluorescence staining of cardiac tissue cryo-sections and immunoblotting were used to assess the intensity of inflammation and autophagy in the epicardium.Results. Inflammation and other signs of acute pericarditis resulting in thickening of some epicardial areas were found: 68+9% in the control (after PBS injection) and 124+22% after Freund's adjuvant injection (p=0.009); other signs included cellular infiltration of epicardium and multiple adhesions. The epicardial layer exhibited signs of mesothelial cells reorganization with 11-fold increase of autophagy markers LC3 II/LC3 I ratio: 0.07+0.02 in the control group (after PBS injection) and 0.84+0.07 - in acute pericarditis (p=0.04), and accumulation of collagen fibers.Conclusion. Development of acute pericarditis is accompanied by activation of epicardial mesothelial cells, intensified autophagy and development of fibrous changes in epicacardial/ subepicardial areas.

Fundamental research in recent years has allowed us to reassess the molecular and cellular mechanisms of cardiac ontogenesis and its repair after damage. The epicardium, the outer, tightly adjoining layer of the cardiac wall formed by epicardial mesothelial cells, collagen and elastic fibers, has gained special relevance as an important participant of reparative processes. Better insight into poorly understood epicardial function is challenged due to anatomical issues and lack of relevant cellular models. The aim of this study was to develop a spheroid 3D model of the epicardial microenvironment and determine responses of spheroids to hypoxia. Materials and methods. Spheroids were harvested in V-shaped culture dishes with a low adhesion coating. Immunofluorescent staining of cryosections, histological methods and real-time PCR were used for characterization of cultured spheroids. Results. We demonstrated that cultivation of cells under low adhesion conditions in V-shaped culture dishes resulted in the formation of spheroids with an average size of 136+21 µm and cell viability rates of over 98%. The cells in the spheroids cultured under normoxic conditions formed tight junctions and were characterized by a low level of proliferation and the ability to synthesize extracellular matrix proteins. Under hypoxia cells in the spheroids showed partial loss of intercellular contacts, acquired a spindle shape, started to express HIF1a, SNAIL, COL1Al and accumulate collagen. All these features demonstrated the activation of mesothelial(endothelial)-mesenchymal transition strongly resembling epicardial cellular responses to ischemia in vivo. Conclusion. An epicardial spheroid cell culture model suitable for study cellular responses to hypoxic environment was developed. This model can be used to clarify mechanisms regulating epicardial microenvironment and test new targeted candidate drugs.

ЦЕЛЬ: исследовать влияние бариатрической операции (БО) на жизнеспособность и пролиферацию мезенхимальных стволовых клеток жировой ткани (МСК ЖТ) пациентов с сахарным диабетом 2 типа (СД2). МАТЕРИАЛЫ И МЕТОДЫ: МСК были получены из подкожной ЖТ пациентов с СД2 до бариатрической операции и спустя полгода после бариатрической операции (пациенты с ИМТ>35 кг/м2, длительность ожирения более 10 лет). Выделение клеток проводили согласно стандартному протоколу с использованием коллагеназы 1 типа. Жизнеспособность клеток оценивали с помощью колориметрического МТТ-теста с предварительной инкубацией клеток в среде с различным содержанием сыворотки – 1% и 10% эмбриональной бычьей сыворотки (FBS). Экспрессию ядерного антигена пролиферирующих клеток (PCNA) определяли с помощью иммуноцитохимического окрашивания и иммуноблоттинга. РЕЗУЛЬТАТЫ: иммуноцитохимическое окрашивание показало, что стимуляция клеток сывороткой демонстрирует более чем в два раза увеличенное содержание PCNA-положительных клеток среди МСК, полученных после бариатрической операции по сравнению с МСК до бариатрической операции. Аналогичные результаты наблюдаются при анализе экспрессии PCNA методом иммуноблоттинга – стимуляция сывороткой способствует большей экспрессии PCNA в клетках пациентов после бариатрической операции. При этом МТТ-тест продемонстрировал увеличение жизнеспособности МСК после бариатрической операции, вне зависимости от процентного содержания сыворотки в среде. ВЫВОДЫ: мезенхимальные стволовые клетки, полученные после бариатрической операции из подкожной жировой ткани пациентов с сахарным диабетом 2 типа, обладают увеличенным пролиферативным потенциалом и жизнеспособностью по сравнению с МСК пациентов до бариатрической операции.

ЦЕЛЬ: изучить роль противовоспалительного цитокина интерлейкина 4 (ИЛ-4) в регуляции энергети- ческого метаболизма и термогенеза в адипоцитах. МАТЕРИАЛЫ И МЕТОДЫ: клетки 3T3-L1 дифференцировали в адипогенном направлении в присутствии инсулина, изобутилметилксантина, дексаметазона и розиглитазона. Зрелые адипоциты стимулировали рекомбинантным ИЛ-4 (50нг/мл) в течение 24ч. Для анализа поглощения глюкозы, липолиза и липогенеза использовали радиоактивномеченные препараты 3Н-2-дезоксиглюкозы и 14С-глюкозы. Морфологию липидных капель и термогенез оценивали с использованием конфокальной микроскопии клеток, окра- шенных флуоресцентными зондами BODIPY и ERthermAC. Для оценки механизмов действия ИЛ-4 на липо- лиз использовали ингибитор липолиза (орлистат), ингибитор адипоцитарной триглицерид липазы ATGL (атглистатин), ингибитор моноацилглицерид липазы MGL (JJKK). РЕЗУЛЬТАТЫ: мы показали, что ИЛ-4 активирует поглощение 3Н-2-дезоксиглюкозы в адипоцитах. ИЛ-4 не оказывает влияние на количество липидов в адипоцитах и активность липогенеза, но приводил к из- менению морфологии липидных капель. В клетках, стимулированных ИЛ-4, снижается количество крупных липидных капель и увеличивается количество мелких. Эффект ИЛ-4 на морфологию липидных капель сни- мается при ингибировании как липолиза в целом, так и ATGL. Ингибирование MGL не оказывает влияние на размер липидных капель. Кроме того, ИЛ-4 активирует термогенез в адипоцитах по ATGL-зависимому механизму. ВЫВОДЫ: стимуляция ИЛ-4 приводит к фрагментации липидных капель в адипоцитах через активацию расщепления триацилглицеридов липазой ATGL, но не MGL. Одновременная активация поглощения глю- козы, липолиза и термогенеза в адипоцитах под действием ИЛ-4 может говорить о стимуляции футильного триацилглицеридного цикла, приводящего к диссипации энергии окислительных процессов в виде тепла.

Neoangiogenesis is the key process determining myocardial regeneration after infarction. The urokinase-type plasminogen activator receptor (uPAR) is known to play an important role in the regulation of endothelial cell function and postnatal angiogenesis. However, uPAR its involvement in the regulation of the properties of vascular progenitor cells remains poorly studied. Aim: to evaluate uPAR expression on the surface of resident cardiac vascular progenitor cells (rcVPCs) and its impact on angiogenic cell properties in vitro as well as postinfarction cardiac vascularization. Materials and Methods. We used immunofluorescent analysis of cryosections of a murine myocardial infarction model to characterize vessels and rcVPCs, and evaluatedв the angiogenic properties potential of vasculogenic progenitor cells using the «tube assay» and induction ofinducing differentiation in a specialized medium. Results. We have found that the majority of Sca-1+ rcVPCs express the urokinase receptor and endothelial cell markers on their surface and are capable of proliferation and integration into the newly formed vessels in the injured area, indicating their possible involvement in thecontribution to vascularization process after infarction. After acute ischemic injury, the accumulation of vasculogenic progenitor cells (8+2 and 27+7 cells per visual field, respectively; P = 0.032) and vascularization processes (85+11 and 166+25 capillaries per visual field, respectively; P = 0.033) were observed in myocardium of uPAR-/- animals, compared with wild-type animals. Our studies demonstrated that Sca-1+ rcVCPs derived from uPAR-/- murine hearts demonstrated a reduced ability to form capillary-like structures and endothelial differentiation compared with Sca-1+ rcVCPs from hearts of wild-type mice. Conclusion. Thus, uPAR deficiency may lead to impaired vasculogenic properties of Sca-1+ rcVCPs, which is likely due to the loss of regulatory influence of specific ligands and the ability to interact with signaling mediators such as integrins. From the viewpoint of regenerative medicine, the modulation of uPAR activity can be considered as a potential targetpromising approach for targeted regulation of vasculogenic progenitor cells properties and postnatal angiogenesis.Highlight The urokinase-type plasminogen activator receptor is involved in the regulation of the angiogenic properties of Sca1+ vasculogenic progenitor cells.

It was suggested that the urokinase system plays a certain role in the regulation of activity of the endothelial–mesenchymal transition and in the development of perivascular fibrosis. Urokinase (uPA), the key component of the urokinase system, is a serine protease that binds to its receptor on the cell surface (uPAR) and affects the cell microenvironment components through the formation of plasmin, remodeling of the extracellular matrix, release of growth factors, and initiation of intracellular signals. The heart of PLAUR gene knockout C57BL/129 (uPAR—/—) mice showed signs of vasculopathy: reduced number of capillaries/arterioles, signs of endothelial–mesenchymal transition in endothelial cells, vascular wall remodeling, and deposition of extracellular matrix components. These changes were combined with enhanced expression of urokinase and active forms of TGF-β1. Apparently, uPAR is a part of a multicomponent system that provides multifaceted regulatory effects on the components of forming vessels and vascular wall cells, which allows considering it as a possible target for targeted antifibrotic therapy.

We studied the effect of 3D-culturing of cells in the form of cardiospheres on the expression of genes encoding vascular progenitor cell markers and angiogenesis regulators and on the production of proangiogenic factors. Cardiospheres were obtained by culturing mouse cardiac explants followed by self-assembly on poly-D-lysine. Gene expression was assessed by real-time PCR, and the production of proangiogenic factors was assessed by Microarray analysis of the cell secretome. It was found that cells in the cardiospheres in comparison with 2D-culture of cardiosphere-forming cells demonstrated increased expression of vascular progenitor cell markers ( Pdgfrα , Kit , and Vegfr1 ) and angiogenesis regulatory factors ( Vegf , Fgf2 , and Angpt1 ), as well as an enhanced secretion of proangiogenic factors (ANGPT1, VEGF, CXCL16, and PIGF-2). Thus, culturing of cells in the form of cardiospheres can be considered as a basis for developing approaches to increasing their angiogenic activity and regenerative properties.

The study of the mechanisms of development and progression of fibrosis is one of the key directions of modern cardiology. Our work suggests that the urokinase receptor (uPAR) is involved in the regulation of mesothelial cell activity and epicardial fibrosis development, which, when interacting with specific ligands and intermediate proteins, can activate intracellular signaling, trigger the cascade of proteolytic reactions, including local plasmin formation and activation of matrix metalloproteinases, providing matrix remodeling.Objective: to perform a comparative study of fibrogenic activity of the epicardium in the hearts of uPAR-/- and wild-type animals and evaluate the effect of cardiac microenvironment factors on the migration activity of epicardial mesothelial cells.Material and methods. We used histological and immunofluorescent staining, microarray analysis of proinflammatory cytokine levels, and a method for assessing the migratory properties of epicardial cells.Results. Results. We found that compared to wild-type animals, uPAR-/- animals show significant thickening of the epicardial area (2.46+0.77 (uPAR-/- mice) and 1.02+0.17 (Wt mice) relative units, P=0.033) accompanied by accumulation of extracellular matrix proteins. Deficiency of uPAR gene leads to formation of proinflammatory microenvironment in the heart (increased levels of proinflammatory factors such as IL-1, IL-13, IL-17, RANTES and MIP1), increased migratory activity of epicardial mesothelial cells, accumulation of TCF21+fibroblast/myofibroblast precursors (29.8+13.7 (uPAR-/- mouse) and 3.03+0.8 (Wt mouse) cells per visual field,P=0.02), as well as development of subepicardial fibrosis.Conclusion. These findings suggest that uPAR is a promising candidate for the developing targeted agents to prevent the development and progression of cardiac fibrosis.

Background. The application of tissue-engineered constructs that simulate the natural microenvironment of cells, maintain their viability and functional properties, is a new promising route for the treatment of ischemic diseases. However, the mechanisms that ensure the effectiveness of this type of treatment and the principles of choosing the optimal population of progenitor cells remain poorly understood. Aim. To study the profile of secretion of proangiogenic growth factors of cardiosphere-derived cell sheet (CS), and to study the effect of their transplantation on postinfarction myocardial vascularization. Methods. Assembly of cardiosphere-derived cell sheets were performed on thermosensitive culture plates. Characterization of cell sheets was performed using immunofluorescence staining and a commercial kit for the determination of proangiogenic factors “Mouse Angiogenesis Antibody Array”. The evaluation of the angiogenic properties of the cell graft in vivo was carried out using a rat myocardial infarction model. Results. It was found that the cardiosphere-derived cell sheet secrete factors involved in the regulation of vasculo-/angiogenesis. At the same time, the cultivation of cell sheets under hypoxic conditions (3% O2) led to an increase in the secretion of proangigenic factors VEGF and pIgF, fGf-1, FGF-2, endothelin-1, as well as MMP-9, which is involved in extracellular matrix remodeling. Cell sheet transplantation on the epicardial surface of the heart after myocardial infarction ensures cell viability and local increase in capillarization of the damaged area. Conclusion. Thus, the application of cardiosphere-derived cell sheets, which have proangiogenic properties and ability to maintain post transplantation cell survival, can be considered as a promising approach for the development of new methods of therapy for heart diseases

Increasing incidence of ischemic diseases and limited resources for their treatment stimulate increased interest in studying the mechanisms of vascularization and finding new approaches for its promotion. One of these approaches is gene therapy aimed at activating the epicardium to produce the vascular precursor cells and microenvironment for the «assembly» of de novo vessels.The aim is to investigate the possibility of activating epicardial cells and post infarction cardiac vascularization by injecting a genetic construct encoding PDGFBB.Material and methods. A model of experimental myocardial infarction in a rat with subsequent intramyocardial injection of normal saline solution, control plasmid and plasmid encoding PDGFBB was used. The study of PDGFBB effect on epicardial cell activity was performed on the ex vivo model, as well as in vitro mesothelial cell culture.Results. Post infarction injection of plasmid encoding PDGFBB increases the density of the vascular network in the peri-infarct area as well as migration of pericytes to the injured zone. PDGFBB promotes activation of epicardial cell pool and expression of smooth muscle cell markers in them (shown on the ex vivo model), as well as stimulates activation of epithelial-mesenchymal transition (in vitro).Conclusion. Intramyocardial injection of a genetic construct encoding PDGFBB after an experimental myocardial infarction stimulated vascularization of the peri-infarction zone, which may have been partially due to the activation of the epicardial cell pool.

The aim of the investigation was to study the effect of 2-ethyl-6-methyl-3-hydroxypyridine malate (Ethoxidol) on the concentration of oxidative stress metabolites in patients with chronic heart failure (CHF) and hypertension. Materials and Methods. 126 patients with FC I-III CHF have been examined. In addition to their individual therapy these patients received intravenous infusions of Ethoxidol. Blood content of 2,3-diphosphoglycerate (2,3-DPG), oxygen tension (pO(2)), pH, concentration of total peroxides, lactate, and aldosterone were identified. 2,3-DPG levels (g/L erythrocytes) in whole blood samples were determined by an enzyme assay using the reagent kit (Rosh, Germany), values of pO(2), pCO(2), pH, lactate in the venous blood were measured using gas analyzer Stat Profil pHOx Ultra ( Nova Biomedical, USA). Indices of oxidative stress, i.e. the concentration of plasma total peroxides, were investigated by ELISA using OxyStat kit (Biomedica, Austria). Peripheral venous blood samples were collected from all patients before and 6 days after the daily intravenous Ethoxidol infusion. Results. In patients with FC I, II, III CHF, on day 7 after intravenous Ethoxidol infusion at a dose of 100 mg/day, statistically significant growth (p=0.0002) of PaO2 level by 15.7, 17.4, and 22.8%, respectively, was noted. In patients with FC I, II, III CHF in the group receiving standard therapy, statistically significant (p=0.002) reduction of 2,3-DPG level by 2.7, 2.4, and 4.0%, respectively, was registered. On day 7 after the infusion of Ethoxidol at a dose of 100 mg/day, its decrease by 5.7, 10.5, and 26.2%, respectively (p<0.0001), was also observed. Conclusion. The increased concentrations of active oxygen forms have been established to negatively affect various bodily functions and adversely influence the pathophysiology of numerous diseases. Application of antioxidants, including Ethoxidol presented by us in this article, may become a clue to the development of preventive measures for many serious diseases.

Cardiovascular diseases are the leading cause of morbidity and mortality worldwide. In recent years, researchers are attracted to the use of cell therapy based on stem cell and progenitor cells, which has been a promising strategy for cardiac repair after injury. However, conducted research using intracoronary or intramyocardial transplantation of various types of stem/progenitor cells as a cell suspension showed modest efficiency. This is due to the low degree of integration and cell survival after transplantation. To overcome these limitations, the concept of the use of multicellular spheroids modeling the natural microenvironment of cells has been proposed, which allows maintaining their viability and therapeutic properties. It is of great interest to use so-called cardial spheroids (cardiospheres) spontaneously forming three-dimensional structures under low-adhesive conditions, consisting of a heterogeneous population of myocardial progenitor cells and extracellular matrix proteins. This review presents data on methods for creating cardiospheres, directed regulation of their properties and reparative potential, as well as the results of preclinical and clinical studies on their use for the treatment of heart diseases.

In heart attack, FSTL-1 is actively secreted by cardiomyocytes, accelerates growth of heart myofibrils and stimulates of vascular endothelial growth factor expression. The aim of this work was to investigate the effect of Etoxidol on synthesis of FSTL-1 in rats after myocardial infarction. The experiments were performed on Wistar rats weighing 250-350 g with simulated myocardial infarction or intact (group 5). Animals of control groups (groups 1, 2) were treated with saline for 7 and 14 days; Ethoxidol (24 mg/kg) was injected to animals of experimental groups (group 3, 4) (the daily dose was 6.36 mg/animal) for 6 or 14 days. The injection volume was 0.2 ml. At the beginning and at the end of the study plasma concentrations of FSTL-1 were determined by the ELISA method. Myocardial FSTL-1 gene expression was determined by real-time PCR. At the end of the experiments, the hearts were also used for histochemical analysis. To determine the size of the scar formed after the modeled heart attack, we used the classic Mallory staining method. The results show that the development of experimental acute myocardial infarction is accompanied by a significant increase in FSTL-1 expression in the heart, which was detected on the 7th day and stored increased by 14 days after a heart attack. After therapy with Ethoxidol, a tendency to a decrease in the expression of FSTL-1 by the 14th day was observed; it coincided with the dynamics of the plasma protein FSTL-1 level. It can be assumed that the downregulation trend in the FSTL-1 expression is associated with a more effective repair process after a heart attack, since FSTL-1 increases precisely in response to myocardial damage and decreases when the incentives for its expression from damaged heart tissue are reduced. Indirectly, this assumption is confirmed by the detected tendency to reduce the size of post-infarction fibrosis in the treatment with Ethoxidol. The results indicate the ability of Ethoxidol to influence FSTL-1 synthesis of in rats after myocardial infarction.

Aim : to evaluate the impact of tissue-engineered structures (TES) transplantation based on mesenchymal stromal cell (MSC) sheets in myocardial infarction on the activation of the epicardial cell pool and vascularization of the damaged zone. Materials and methods . Mesenchymal stromal cells were obtained from samples of subcutaneous fat of Wistar rats and C57Bl/6 mice. Tissue engineering structures were obtained by culturing cell sheets on thermosensitive plates (Nunc Dishes with UpCell Surface). Transplantation of TESs was performed after myocardial infarction modeling in rats by ligation of the anterior descending coronary artery. Transplant cells and damaged zones were assessed using immunofluorescent staining of myocardial cryosections. The impact of MSC secretion products on the migration activity of epicardial cells in vitro was evaluated using the explant culture method. Results . MSCs in TESs after transplantation remain viable and induce activation of the epicardial cell pool and local increase of the damaged zone vascularization. The in vitro experiments showed that the conditioned environment of MSCs stimulates the migratory activity of epicardial cells and initiates the formation of activated Wt1/POD1 precursor cells. Conclusion . TES transplantation on the basis of MSC sheets seems to be a promising approach for effective delivery of viable cells into myocardium to activate the epicardial cellular niche and reparative angiogenesis.

A stimulating effect of a combination of hepatocyte growth factor (HGF) and glial neurotrophic factor (GDNF) on the growth of neurites in the spinal ganglion model was demonstrated. The mechanism of neurite growth in the spinal ganglion model is associated with transactivation of HGF c-met receptor in the presence of both HGF and GDNF. The combination of HGF and GDNF significantly activated mitogenic signaling cascade mediated by protein kinases ERK1/2, which can be a mechanism for increasing the number of neurites. Our findings can be used for developing effective methods for restoring impaired peripheral nerve function after traumatic and ischemic injury using a combination of GDNF and HGF.